Machines, such as, hydraulic excavators, hydraulic shovels, backhoe loaders and the like, are often required to perform different kinds of work on a work site. Therefore, different work tools, such as buckets, hammers, rippers, and grapples, may have to be engaged with an arm assembly (including, for example, sticks and booms) of the machine. It is known that the process of removing one work tool from the arm assembly and replacing the work tool with a different work tool may be a time consuming and difficult process. Quick couplers have been employed to enable quick engagement of the stick and the work tool and the quick couplers do, to an extent, reduce effort required for removing the work tool and replacing it. However, such quick couplers add weight to the stick end and build up the stick height/length. As a result, the machine's capabilities may be compromised.
For example, U.S. Pat. No. 7,014,385 B2 discloses an attachment coupling device for heavy machinery. The attachment coupling device is designed to releasably connect a variety of attachments to an arm and a push link of heavy machinery, such as hydraulic excavators. The attachment coupling device comprises a pair of mounting brackets fixedly secured to the attachment, each bracket having first and second hooks spaced apart with each other. Another major element of the coupling device is a coupler which includes, a fixed plate affixed to the arm and the push link, a pair of fixed coupling pins each protruding outwardly from the fixed plate for engagement with the first hook of each of the mounting brackets, a pair of movable coupling pins for movement between a retracted release position and an extended coupling position, wherein the respective one of the movable pins comes into engagement with the second hook of each of the mounting brackets, and an actuator for causing movement of the movable coupling pins.